Lynch, the U.S. attorney in Brooklyn, New York, is President Barack Obama’s pick to succeed Holder at the helm of the Justice Department, a post that has increasingly become fraught with political controversies and clouded by Holder and Congress’ mutual contempt for each other.

“The message has already been received: if you cross the administration with perfectly accurate reporting that they don’t like: you will be attacked and punished,” Attkisson said Thursday before the Senate Judiciary Committee.

That question, posed to Loretta Lynch nearly two hours into her confirmation hearing to be the next attorney general, seemed to encapsulate what every Republican on the Senate Judiciary Committee was likely thinking.

Multiple GOP senators used Lynch’s confirmation hearing to press her on Obama’s executive actions on immigration, although she said little beyond calling the administration’s legal rationale for the actions “reasonable.” Her refusal to weigh in much further visibly frustrated some Republicans, who have been the biggest critics of the president’s efforts to stop deportations for nearly 5 million immigrants who are here illegally.

Her statement came after Sen. Patrick Leahy (D-Vt.) asked whether she believed waterboarding was torture. Leahy also referred to the report on enhanced interrogations that the Senate Intelligence Committee — then under Democratic control — released in December.

“I look forward to fostering a new and improved relationship with this committee, the United States Senate, and the entire United States Congress,” Lynch said as the Senate Judiciary Committee began a two-day hearing on her confirmation.

Lynch, who is set to face a tough hearing for the post, started a chapter of the sorority at Harvard with current Attorney General Eric Holder’s wife, Sharon Malone. Though the connection was seen as controversial to members of the right-wing media, her sorority sisters proudly donned the organization’s signature colors—crimson and cream—in the hearing room.

Republicans have been particularly critical of the president’s decision last year to unilaterally ease the threat of deportation for millions of unauthorized immigrants. Attorney General Eric H. Holder Jr. approved the legal justification for that action.

The U.S. Attorney’s office in Brooklyn quietly retreated on what it has once described as a major case, in wake of civil forfeiture controversy and just before hearings for the Attorney General nominee.

The conviction is a significant victory for the Obama administration, which has led an unprecedented crackdown on officials who speak to journalists about security matters without the administration’s approval. Prosecutors prevailed after a yearslong fight in which the journalist, James Risen, refused to identify his sources.

The arrest of Mr. Silver, a Democrat from the Lower East Side of Manhattan who has served as speaker for more than two decades, sent shock waves through the political establishment and upending the new legislative session.